Numerous types of systems include automated processes to generate one or more parameters which may be used to evaluate the current state of the system. The automated process may also be used to improve system performance or even repair certain defects or faults. For example, a data storage drive, such as a tape drive, may include an adaptive equalizer with many finite impulse response (FIR) taps whose input coefficients are automatically modified to optimize system performance.
However, it may be difficult to assess the quality of the result of an automated process because of obscure relationships between the measured parameters and the system response. It will be appreciated that if the integrity of the parameter values is not verified, there is a risk that the automated process produces an undesirable system response. Thus, not only might the process fail to improve performance but, if the parameter values are undetectably invalid, may also cause the system to fail completely.
For example, in an adaptive equalizer of a tape drive, FIR tap values are computed from information captured from the storage drive. If the information is corrupted, or if execution of the algorithm which is used to compute the tap values is corrupted, the FIR tap values will be invalid. More specifically, a media defect or servo error may corrupt the captured information. Similarly, an overflow or underflow may occur during the execution of the FIR tap algorithm, resulting in tap values which bear no relation to the proper results. Or, rather than the captured information being invalid, the information may result in the creation of tap values which are outside the range of values which can be handled by the equalizer. In each of these circumstances, the invalid or improper condition of the tap values may be undetected.
Consequently, there remains a need for an automated process which provides an assessment of the quality of parameter values which are used to adjust the system.